/*    Copyright 2012 10gen Inc.
 *
 *    This program is free software: you can redistribute it and/or  modify
 *    it under the terms of the GNU Affero General Public License, version 3,
 *    as published by the Free Software Foundation.
 *
 *    This program is distributed in the hope that it will be useful,
 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *    GNU Affero General Public License for more details.
 *
 *    You should have received a copy of the GNU Affero General Public License
 *    along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 *    As a special exception, the copyright holders give permission to link the
 *    code of portions of this program with the OpenSSL library under certain
 *    conditions as described in each individual source file and distribute
 *    linked combinations including the program with the OpenSSL library. You
 *    must comply with the GNU Affero General Public License in all respects
 *    for all of the code used other than as permitted herein. If you modify
 *    file(s) with this exception, you may extend this exception to your
 *    version of the file(s), but you are not obligated to do so. If you do not
 *    wish to do so, delete this exception statement from your version. If you
 *    delete this exception statement from all source files in the program,
 *    then also delete it in the license file.
 */

#include "mongo/db/auth/user_set.h"

#include <string>
#include <vector>

#include "mongo/db/auth/authorization_manager.h"
#include "mongo/db/auth/user.h"

namespace mongo {

namespace {
    class UserSetNameIteratorImpl : public UserNameIterator::Impl {
        MONGO_DISALLOW_COPYING(UserSetNameIteratorImpl);
    public:
        UserSetNameIteratorImpl(const UserSet::iterator& begin,
                                const UserSet::iterator& end) :
            _curr(begin), _end(end) {}
        virtual ~UserSetNameIteratorImpl() {}
        virtual bool more() const { return _curr != _end; }
        virtual const UserName& next() { return (*(_curr++))->getName(); }
        virtual const UserName& get() const { return (*_curr)->getName(); }
        virtual UserNameIterator::Impl* doClone() const {
            return new UserSetNameIteratorImpl(_curr, _end);
        }

    private:
        UserSet::iterator _curr;
        UserSet::iterator _end;
    };
} // namespace

    UserSet::UserSet() : _users(), _usersEnd(_users.end()) {}
    UserSet::~UserSet() {}

    User* UserSet::add(User* user) {
        for (mutable_iterator it = mbegin(); it != mend(); ++it) {
            User* current = *it;
            if (current->getName().getDB() == user->getName().getDB()) {
                // There can be only one user per database.
                *it = user;
                return current;
            }
        }
        if (_usersEnd == _users.end()) {
            _users.push_back(user);
            _usersEnd = _users.end();
        }
        else {
            *_usersEnd = user;
            ++_usersEnd;
        }
        return NULL;
    }

    User* UserSet::removeByDBName(const StringData& dbname) {
        for (iterator it = begin(); it != end(); ++it) {
            User* current = *it;
            if (current->getName().getDB() == dbname) {
                return removeAt(it);
            }
        }
        return NULL;
    }

    User* UserSet::replaceAt(iterator it, User* replacement) {
        size_t offset = it - begin();
        User* old = _users[offset];
        _users[offset] = replacement;
        return old;
    }

    User* UserSet::removeAt(iterator it) {
        size_t offset = it - begin();
        User* old = _users[offset];
        --_usersEnd;
        _users[offset] = *_usersEnd;
        *_usersEnd = NULL;
        return old;
    }

    User* UserSet::lookup(const UserName& name) const {
        User* user = lookupByDBName(name.getDB());
        if (user && user->getName() == name) {
            return user;
        }
        return NULL;
    }

    User* UserSet::lookupByDBName(const StringData& dbname) const {
        for (iterator it = begin(); it != end(); ++it) {
            User* current = *it;
            if (current->getName().getDB() == dbname) {
                return current;
            }
        }
        return NULL;
    }

    UserNameIterator UserSet::getNames() const {
        return UserNameIterator(new UserSetNameIteratorImpl(begin(), end()));
    }
} // namespace mongo
